


Favourite Pastime

by hookedonthesky



Category: Harry Potter - J. K. Rowling
Genre: Academic rivals, F/F, Female Harry Potter, Female Harry/Tom, Female Tom Riddle, Harry Potter & Tom Riddle Attend Hogwarts Together, Hate Sex, Rivalry, cos_winterexchange2019, same age au
Language: English
Status: Completed
Published: 2019-12-24
Updated: 2019-12-24
Packaged: 2021-02-26 02:42:25
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,158
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21944317
Author URL: https://archiveofourown.org/users/hookedonthesky/pseuds/hookedonthesky
Summary: Harry Potter hated Tamsin Riddle. She hated her smug looks, her superior attitude and her perfect attire. But Harry also loved getting one over Tamsin. Academically, or... otherwise, Harry, well, Harry loved to win.
Relationships: Harry Potter/Tom Riddle
Comments: 2
Kudos: 82
Collections: Chamber of Secrets' Winter Exchange (2019)





	Favourite Pastime

**Author's Note:**

  * For [wulcanbiology](https://archiveofourown.org/users/wulcanbiology/gifts).

Harry wanted to scream. That infuriating smirk kept replaying over and over in her mind as she sped towards her common room. 

_ “What’s wrong, Potter? Oh, you couldn’t do the complete transfiguration?” _

Harry shook her head, as if trying to remove the memory, but there was no use. Riddle knew _ exactly _ how to get under her skin. Harry hated it.

Reaching the Fat Lady, Harry felt a stab of guilt for leaving Hermione and Ron and storming off, but it was fleeting. They… well, they wouldn’t understand, but they wouldn’t mind. As much as she hated it, Harry was aware that they were already used to situations like this. 

If someone had told Harry when she had started Hogwarts that she would get so worked up over academics, she would have laughed in their face. And she hadn’t cared much in the beginning, she could remember how in their first year, she’d already been prepared to spend evenings wasting time with Ron in their common room in lieu of studying, and doing everything last minute. But then… Tamsin Riddle happened.

Harry, already furious, could feel her blood boil as she recalled that first interaction, at the end of their first year. Harry hadn’t paid much attention to most Slytherins before that point, except Draco Malfoy who was more of a nuisance than anything, when a smug Slytherin girl that Harry never even met before that point decided to make fun of Harry and her “mediocre performance.” With that _ infuriating _smirk of hers, and some other Slytherin girls tittering behind her, she informed Harry that maybe she should try taking better care of her appearance, as it seemed that her skill in magic wouldn’t get her far. Harry had heard plenty of insults from Slytherins before, especially when she got to be the Gryffindor seeker in her first year, but for some reason, Riddle managed to get under her skin better than anyone else did. So much in fact, that Harry had spent the whole summer after first year studying, catching up on everything that she’d missed and continuing in the same manner once second year started. It had been gruelling work, especially since Harry didn’t find the same joy in studying as Hermione did, but it was all worth it the moment she’d managed to learn a complicated transfiguration spell before Riddle. Riddle’s shocked expression still brought pleasure to Harry when she thought about it.

Since then, they’d become something akin to rivals. Harry would’ve never thought she would be one of the people vying for best performance in their year, but every success, every win against Riddle brought almost unparallel pleasure to Harry. Of course, it worked both ways, as every loss and every smug smirk Riddle made Harry _ furious. _

Having reached the common room, Harry stormed up the stairs and threw herself on her bed. She had two free hours and she had planned to revise during them, but she was still fuming, Riddle’s self-satisfied face greeting her every time she closed her eyes. Harry hadn’t even gotten the prefect badge last year! That was still a sore point for her, especially since Riddle took every chance she could to lord it over her. Harry was well aware that Hermione deserved it too, and that Harry got to be Quidditch captain instead and that being a prefect on top of that would have been hard. But if only Riddle would stop being so _ smug _ all the time. Next year the staff would choose Head Boy and Head Girl, and Harry _ had _ to get it. She just had to prove to McGonagall that being a Quidditch captain and a Head Girl at the same time is completely doable and… Harry shook her head again, forcefully expelling those thoughts from her head. Dwelling wouldn’t make her feel better now, she just had to be _ better. _

Harry looked up as she heard someone entering the dormitory. It was Hermione, and Harry looked away with a mulish frown, wishing she hadn’t come. She knew what Hermione would say.

“You shouldn’t let her affect you so much,” said Hermione, not unkindly. There was still reproach in her voice that made Harry clench her fists.

“I’m fine,” Harry bit out, clearly not fine.

“Harry,” Hermione insisted, “I know this… _ thing _you two have has been going on for a while, but I really don’t think getting so angry is worth it.”

“I said I’m fine!” Harry said, harsher than intended. She winced, suddenly feeling guilty again, and forced herself to calm down, trying for an apologetic smile. “Sorry, I didn’t mean it like that. I just… I’ll be down soon. Just need a second alone, please.”

“Alright,” said Hermione, caving. “I’ll be in the common room, with Ron.”

She hesitated for a second, that said, “You know I’m here if you want to talk, right?”

“Yeah, I know. Thanks Hermione,” Harry replied, smiling more genuinely this time.

After watching Hermione leave, she gave a sigh. Hermione didn’t understand, not really. She had been thrilled, back in second year, when she’d realised that Harry had finally decided to take studying magic seriously. She had always griped at her and Ron during first year for not studying enough, and Harry’s change of heart had been very welcome, at first. Ron hadn’t accepted it that well, missing his chess partner, but he quickly accepted Harry wanted to study with Hermione as well, them being girls.

But as years passed, and Harry kept complaining about Riddle, and studying because of Riddle, and in general focusing so much on her, Hermione and Ron had started getting increasingly fed up. Harry tried talking less about Riddle, but she _ couldn’t _ help just how angry she made her, with her always perfectly styled hair and comments that made Harry want to throttle her. Hermione had tried comparing it to Malfoy, and how the insults had stopped once they got older and “why can’t you and Tamsin act maturely as well, Harry?” But Hermione just didn’t get it, Malfoy, and most of the other Slytherins were nuisances, they were _ unimportant, _while Riddle was… Riddle was something else.

With another, longer sigh, Harry sat up. She couldn’t spend any more time wallowing. Riddle’s face flashed in her mind’s eye again, and she felt determination filling her. She was consistently better than Riddle in Defense, but with everything else, it was a struggle. And she _ couldn’t _let Riddle humiliate and show her up again like today. So she headed downstairs, hoping that Hermione might want to help her with Transfiguration. She had to figure out what went wrong today, and how she could prevent it from happening ever again.

***

Madam Pince frowned at her, and Harry, after checking the time, realised that it was nearing curfew and time to go. She had told Hermione to leave without her, but she was glad she’d stayed a bit longer as she finally felt like she managed to crack the spell that had been bothering her. With a content sigh, she gathered her books and bid goodbye to Madam Pince who just grunted something, looking at her suspiciously, as usual. 

As she left the Library, Harry stole a glance at the Marauder’s Map, smiling at what she saw. It was _ finally _time. Thankful that she had sent Hermione ahead, instead of going towards the Gryffindor Tower, she took a small detour.

Harry could feel both excitement and anger fill her, as she came closer and closer to her destination. Before going around the final corner, she took a deep breath to compose herself, and then continued.

Tamsin Riddle looked up from where she was leaning against the window as soon as Harry saw her, as if she was expecting her. She was dressed immaculately, in finely pressed robes and with a perfectly styled brown bob that seemed to be the new popular thing in pureblood circles. When they had been younger, Harry had felt self-conscious about her long, dark, untamable hair, and had hated Riddle for how she always managed to look perfect, but she ignored that now as she strode resolutely towards Riddle.

“Hello, Potter. Careful, wouldn’t want to overstep the curfew, now do you? I’d hate it if I had to report you.” 

Instead of acting on her threat, however, Riddle continued to stand where she was, casually leaning against a wall.

“Sorry for interrupting your rounds then, Riddle,” Harry replied, walking slowly towards her. “I’m heading towards my common room, so no need to worry about me missing the curfew.”

Riddle inclined her head, even though they were both aware they weren’t anywhere near the Gryffindor Tower.

“Coming from the Library? You need all the help you can get, with that dismal performance today,” Riddle said, her lips stretching into a small, familiar smirk.

Harry bared her teeth back at her, in the approximation of a grin, “You should probably worry about yourself, with how soundly I beat you in the duel during Defence yesterday.”

Riddle’s eyes flashed, and she opened her mouth to reply, but Harry had already reached her and she swallowed the reply by smashing her mouth into Riddle’s. She wasn’t being gentle, biting Riddle’s lip and moving her mouth harshly, pouring out all of her aggression and anger into the kiss. Riddle responded in kind, taking a step forward, so that their breasts rubbed against each other and Harry suppressed a moan. 

For a second, she lost herself in the kiss, falling into the familiar battle for dominance, as they kissed anything but gently. However, she rose out of her stupor quickly when she felt that Riddle was manoeuvring them. But Harry was too late to stop it, and feeling Riddle backing her into a corner she broke the kiss and met Riddle’s eyes. Riddle smirked, the same, smug little smirk that Harry felt Riddle reserved only for her. The smirk that Harry hated, but which had also recently started to make heat curl in her belly. And she was sure Riddle _ knew _how much it affected her. 

Riddle wedged a knee between Harry’s, planning to rub it against Harry’s panties as she usually liked to do. However, instead of feeling damp cotton, she felt only wet skin and heat. Harry felt a spike of pleasure, but she controlled her reaction, looking at Riddle’s face closely. Riddle let out a small “oh” and her cheeks flushed, her eyes widening as Harry rubbed herself against Riddle’s knee a bit more.

This time, it was Harry’s turn to smirk as she used Riddle’s moment of weakness to flip them around. She brought her face close to Riddle’s and whispered, “What’s wrong, _ Riddle? _”

Harry took a moment to slip her fingers underneath Riddle’s skirt and into her panties, finding her already very wet, as she’d expected. Feeling victorious, Harry continued, “Wondering how long I’ve been walking around like this? During dinner, or even earlier, during class? Could you have slipped your hand underneath my skirt and found me already wet and ready?”

Riddle tried to glare at her, but her eyes were glazed with pleasure and Harry could see her biting her lip to try and stop moans from escaping. During one of their previous meetings, Riddle had let slip something about Harry walking around without panties. Although she quickly tried to dismiss it, Harry took note of it and by Riddle’s current reaction, she was glad that she’d decided to test this theory. 

As Riddle trembled against her, Harry moved a finger around Riddle’s clit in circular motions, feeling her own wetness dripping down her leg and heat curling in her belly. She wanted Riddle to touch her so bad, but she wanted to _ win _even more.

But Riddle wouldn’t be so easily defeated. Trembling as she was, she still arched up and started sucking on that sensitive spot underneath Harry’s ear, and it took all of Harry’s strength not to moan. She <strike>loved</strike> hated the way Riddle knew all of her weak spots. But she couldn’t, _ wouldn’t _give up now, and with the hand that wasn’t under Riddle’s skirt she directed Riddle’s face towards her, kissing her savagely. The kiss was similar to the first one, all anger and teeth, and Riddle responded in kind. Harry could feel Riddle shifting as if she wanted to change their position, but Harry wasn’t done yet. She curled her fingers in the way she knew Riddle liked, pressing her thumb against Riddle’s clit at the same time. 

This resulted in a long moan from Riddle that was swallowed by Harry’s mouth. Harry smiled savagely, nipping at Riddle’s lips, the movement of her fingers not stopping. She _ had _ her this time. As met Riddle’s eyes again, finding them half-lidded and glazed, she could feel satisfaction filling her. She _ loved _seeing Riddle so debauched, so out of control. Winning against Riddle, academically or at… other things, would never stop being one of her favourite pastimes.

**Author's Note:**

> Aaaah I'm so so sorry this is late. I wanted to get this before reveals, I swear, but I misunderstood when they happen. 
> 
> Hope you like it still, and I hope this fits the prompts well! I've never written fem!Harry/fem!Tom before, so I hope it's good enough. And I love this verse too, and have so many ideas for it, so I might revisit it with something longer in the future!


End file.
